Reactive oxygen species-mediated signaling during abiotic stress

Abstract Abiotic stress causes alterations in physiological, biochemical and metabolic equilibrium in the plant cells, leading to reduction in protein turn-over, change in post translational modification of proteins, impaired photosynthetic capability and increase in ROS production. The stress-induced ROS at higher levels can trigger oxidation of biomolecules, decomposition of membranes, inactivation of enzymes and alteration in gene expression. On the other hand, ROS is also detected by its sensors and signal transduction pathways are activated, which further transports the signal to the nucleus through redox reactions and involvement of Mitogen-activated Protein Kinase (MAPK) pathway. Consequently, change in gene expression patterns is instigated by involvement of stress-regulated cis-acting elements (ARE, CORE, W-box, GCC box, as-1 like) and stress-responsive transcription factors (NAC, MYB, WRKY, RAV, bZIP, AP2/ERF, ZAT). Finally, these gene products are transmitted back to the cell organelles to facilitate prevention from oxidative damage. Additionally, epigenetic changes play a central role in mediating cellular responses to abiotic stresses. Here, we review the recent updates on ROS-mediated signaling and monitoring of transcriptional and epigenetic changes that occur in a cell due to oxidative stress.